Rifamycin derivative that inhibits bacterial RNA polymerase (same mechanism as rifampicin) but is not absorbed from the GI tract — provides exclusively luminal antibacterial activity. No systemic effects or drug interactions.
At a glance
Class
Non-Absorbable Rifamycin Antibiotic
Storage
Store at room temperature below 30°C
Dosing
Used for hepatic encephalopathy (reduces ammonia-producing bacteria), small inte
Off-label for hepatic encephalopathy and chronic GI bacterial issues
Safety
Clinical response (stool quality, encephalopathy grade)Ammonia levels (hepatic encephalopathy)
Interactions
No documented interactions.
FAQs
Frequently asked questions
›What is Rifaximin?
Rifaximin is a non-absorbable rifamycin antibiotic used in pets. Rifamycin derivative that inhibits bacterial RNA polymerase (same mechanism as rifampicin) but is not absorbed from the GI tract — provides exclusively luminal antibacterial activity. No systemic effects or drug interactions.
›What is Rifaximin used for in pets?
Rifaximin is used in veterinary medicine for: Used for hepatic encephalopathy (reduces ammonia-producing bacteria), small inte; Off-label for hepatic encephalopathy and chronic GI bacterial issues.
›What is the Rifaximin dose for dogs?
For dogs, Rifaximin is typically dosed as follows — Used for hepatic encephalopathy (reduces ammonia-producing bacteria), small inte: 10–25 mg/kg PO q8–12h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Rifaximin dose for cats?
For cats, Rifaximin is typically dosed as follows — Off-label for hepatic encephalopathy and chronic GI bacterial issues: 10–15 mg/kg PO q12h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›Does Rifaximin need a prescription?
Yes. Rifaximin is a prescription medication and should only be administered under veterinary supervision.
References
References
Textbooks & handbooks
- Plumb, D.C. Plumb's Veterinary Drug Handbook. 10th ed., Wiley-Blackwell, 2023.
- Vail, D.M., Thamm, D.H., & Liptak, J.M. (eds.). Withrow & MacEwen's Small Animal Clinical Oncology. 6th ed., Saunders/Elsevier, 2020.
- Riviere, J.E., & Papich, M.G. (eds.). Veterinary Pharmacology and Therapeutics. 10th ed., Wiley-Blackwell, 2018.
- National Research Council. Nutrient Requirements of Dogs and Cats. National Academies Press, Washington DC, 2006.
- The Merck Veterinary Manual. Merck & Co., Online edition. https://www.merckvetmanual.com/
Clinical guidelines & consensus
- Fletcher, D.J., Boller, M., Brainard, B.M., et al. "RECOVER Evidence and Knowledge Gap Analysis on Veterinary CPR." Journal of Veterinary Emergency and Critical Care, 2012;22(S1):S102–S131.
- American Animal Hospital Association. 2018 AAHA Diabetes Management Guidelines for Dogs and Cats. AAHA Press.
Journals & peer-reviewed studies
- Hogan, D.F., Fox, P.R., Jacob, K., et al. "Secondary prevention of cardiogenic arterial thromboembolism in the cat: The FAT CAT study." Journal of Veterinary Cardiology, 2015;17(Suppl 1):S306–S317.
- Boswood, A., Häggström, J., Gordon, S.G., et al. "Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study — A Randomized Clinical Trial." Journal of Veterinary Internal Medicine, 2016;30(6):1765–1779.
- ASPCA Animal Poison Control Center. Toxicology and Poison Management Guidelines. American Society for the Prevention of Cruelty to Animals. https://www.aspca.org/pet-care/animal-poison-control
Regulatory & approvals
- Central Drugs Standard Control Organisation (CDSCO), Government of India. Veterinary Drug Approval Registry, 1969–2026. Directorate General of Health Services. https://cdsco.gov.in/
Databases
- Washington State University, College of Veterinary Medicine. Veterinary Clinical Pharmacology Laboratory (VCPL) — MDR1 Multidrug Sensitivity Database. https://vcpl.vetmed.wsu.edu/
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
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